Step-by-step electric seam-welding apparatus.



No. 853,241. PATENTED MAY 14, 190'7.

H. HELBERGER. l

STEP-BY-STEP ELECTRIC SEAM WELDING APPARATUS.

- APPLICATION FILED sEPT.19, 1906.

2 SHEETS-SEEE?! 1,

"iii-l lilwwr u EME) PATENTED MAY 14, 1907.

H. HELBERGER.

STEP-BY-STEP ELEGTRC SRAM WELDING APPARATUS.

APPLICATION FILED SEPT.19,1906.

2 SHEETS-SHEET 24 described and pointed out amperage.

. UNITED vSTATES PATENT OFFICE.

HUGO HELBERGER, OF MUNICH, GERMANY.

STEPfBY-STEP ELECTRIC SEAM-WELDING APPARATUS.

Specification of Letters Patent.

Patented May 14, 190'?.

ippiicauon flied september 19, 1906. serai No. 335,273.

.do hereby declare the following to be a full,

clear, and exact description of the same, rel erence being had to the accompanying drawings, forming apart of this specification, and to the figures and letters of reference marked thereon.

This invention relates to electric welding machines the objects of the invention bein to provide a means whereby longitudina welded seams or unions'mayv be made in a rapid thorough and-economical manner, to which ends the invention consists in a means whereby the seam or union is formed by a succession of welds which may be spaced apart after the manner of rivets or may overlap or oin to form continuous welds.

The invention further consists in certain novel details of construction and combinations and arrangements ofthe mechanism constituting the machine all as will be now particularly in the appended claims.

In the accompanyin 4drawings-Figure 1 is a side elevation part y in section of a machine for carrying the present invention into practice. Fig. 2 is a to plan`view partly in section of the machine s own in Fig. 1. Fig. 3 is an elevation partly in section of a modified form of .machine desi ned particularly for formin seams of smalI articles orlight sheet meta Fig. 4 is an elevation partly in section taken in a plane at'right angles to Fi .3.

imilar letters of reference in the several figures indicate like parts.

The apparatus illustrated'embodies a welding transformer T Fig. 1, of known construction adapted to convert high potential current into current of lower potential and great Substantially rigid pole eXtensions V V extend in substantial parallelism from the transformer in position to permit the work to pass between them andthe con.- tact pieces K and K kare mounted on said extensions or arms in position to contact f circuit, feed the work with relation to the contacts and where desired open and close the contacts on the worktl1us the cam N3 periodically closes the switch A; the cam N2 periodically moves the feed lever'H and the cam N through the lever H and spring F o erates to reciprocate the contact piece i.

`Said parts aretimed to operate in sequence thusthe contacts are first closed on the work, then the switch is closed and again opened before the contacts separate and the feed lever is operated to feed the work when both the contacts and switch are open.

Thile it is preferred that the contacts shall be opened and closed periodically, it is obvi ous that they may rest againstthe 'work atV all times and have the work drawn between them, the movement away from each other only releasing the work sufficiently to permit the feed to take place. This is advantageous in that the electrodes are polished ,by contact withthe work and when heavy clamping action is not desired the mechanism for moving the contacts apart may be dis ensed with. l

{farious arrangements whereby the work and transformer may be fed or moved with relation to each .other may be employed, a simple arrangement being shown by way of illustration. In the arrangement illustrated, the work, a sheet metal cylinder 0r pipe the overlapping or abutting edges of which are to beunited, is mounted on a carriage C and a rack bar Z adapted tobe engaged by a pawl or dog S on the lever H is connected with the carriage, whereby when the lever is reciprocated the work is given a step by step feed. The particular manner of'mounting the rack bar is not material, thus it may be connected with the carriage through the work itself to which the rack bar is clamped by hand v clamps z, but it will be understood that any well known intermittent lfeed mechanism may be employed,' the particular feature of the present invention being the step by step welding of a seam without regard to the particular mechanism and regardless of whether the work or. the contacts or both are moved in securing the desired relative feed movement of the contacts and work.

In operation, the overlapped or abutted IOO edges of the sheet metal are inserted between the contacts K, K and by them pressed firmly together. Rotation of the shaft establishes the circuit and a current shock passes from one contact to the other through IIO rivets or the feedvmay be short and the welding areas overlapped to form a continuous weld or seam which 1s tight throughout.

In Flgs. 3 and 4 an arrangement 1s shown wherein the transformer S is located in a casing or housing K and th'e polar arms or extensions A, A/ pass out of the cas1ng,one A being rigid and the other-A jointed at D whereby it maybe moved about a fixed axis. i

Oscillatory movement is imparted by the eccentric disk E engaging the rear end of the pivoted part of the arm A. The shaft X carrying the cam disk E is in this instance also provided with a cam disk N for actuating the switch Y for the primary of the transformer andthe adjustments-are such that the cur-v rent is established when the contacts on the arms are pressed toward each other and the current is interrupted before the arms separate.

A Worm feed mechanism such as in Figs. l

p and 2 may be employed or when the seam is their separation.

small or curved manual feed may be resorted to. For convenience in starting and stopping the machine a friction clutch F2 is provided, Vadapted to be operated by a treadle lever F3. g

If an electric arc forms in the switch the weld isnot as effective as when the current is interrupted quickly and at the proper instant and hence it is desirable to employ means for preventing such larcing. The desired result may be secured by employing a spark. or arc extinguisher consisting of a blower G which creates a strong air current across the switch points at the moment of The blower may as shown be operated from themain shaft andthe result is a precise interruption of the current giving the most effective results.

Having thus described my invention,A what I claim and desire to secure by Letters Patent, is

i. An apparatus for electrically welding seams to unite edgeslof sheets of metal7 embodying electrodes having' contact faces forming positive and negative electrodes respectively in opposition to each other, and, movable toward and lfrorneach other to seesaei clamp or release the work between said contact faces, means for moving said electrodes toward and from each other periodically and means for establishing the circuit through said electrodesy when the work isv clamped between them, ysaid means being adapted to break the circuit before the work is released and to only establish the same after the work is' clamped between the electrodes.

2. An electric step by step seam welding apparatus embodying electrodes having'proximate work contacting faces located opposite to each other and forming positive and negative electrodes respectively movable toward and from each other and between which the work is'fed and clamped intermittently and a periodically acting switch timed to interrupt the current while the electrodes are separated.

3. An electric step by step seam welding apparatus embodying electrodes Vhaving` proximate work contacting faces located opposite to each other and forming positive and negative electrodes respectively, means for moving said electrodes toward and from each other and an intermittent work feeding mechanism timed to feed the work between the electrodes ywhen the electrodes are moved away from each other.

4. An electric step by step seam welding apparatus embodying electrodes having proximate work contacting faces located opposite each other and forming positive and negative electrodes respectively, means for periodically moving said electrodes toward and from each other to clamp the work between said faces, an intermittent work feeding mechanism timed to feed the work between the electrodes when the electrodes are moved away from each other and an intermittently operating switch timed toy establish the circuit and permit a welding current to iiow only when the electrodes are pressed toward each other.

5. An electric welding apparatus embody- -ing work feeding mechanism., contacts having work contacting faces located opposite to each other and coperating with opposite sides of the 'work being fed both during the welding and during the feed movements of the work whereby the electrodes are polished but movable toward and from each other to clamp or release the work and an intermittently operating switch timed to interrupt the current during the feed movements of thework.

' HUGO HELBERGER.

`Witnesses :LoUrs MUELLE,

ULYssas J. Brwnrnm 

